Dry phantom for magnetoencephalography -Configuration, calibration, and contribution.
Daisuke Oyama1, Yoshiaki Adachi1, Masato Yumoto2
1Applied Electronics Laboratory, Kanazawa Institute of Technology, 3 Amaike, Kanazawa, Ishikawa 920-1331, Japan.
Journal of Neuroscience Methods
|May 20, 2015
Summary
A new calibrated phantom improves magnetoencephalography (MEG) system evaluation. This phantom offers greater accuracy and detailed uncertainty information compared to uncalibrated models, ensuring more reliable MEG measurements.
Area of Science:
- Biomedical Engineering
- Neuroscience Instrumentation
Background:
- Magnetoencephalography (MEG) systems require phantoms for accuracy evaluation.
- Previous phantoms lacked guaranteed accuracy, compromising MEG system assessment.
- A novel, calibrated phantom is needed to ensure reliable MEG evaluations.
Purpose of the Study:
- To develop a novel, calibrated artificial phantom for MEG systems.
- To demonstrate the advantages of using a calibrated phantom for MEG evaluation.
- To provide detailed uncertainty information for both phantom and MEG measurements.
Main Methods:
- Fabricated a dry phantom with 50 isosceles-triangle coils based on Ilmoniemi's model.
- Calibrated the phantom using 3D current path measurements and numerical calculations.
- Evaluated MEG system performance using the calibrated phantom.
Main Results:
- Calibrated equivalent current dipole (ECD) positions shifted 0.83mm from designed positions on average.
- Quantified uncertainties of calibrated ECDs by combining attribution uncertainties.
- Demonstrated differing MEG evaluation results compared to uncalibrated phantoms.
Conclusions:
- The calibrated phantom provides more appropriate evaluation of MEG measurements.
- It offers detailed information on measurement and phantom uncertainties.
- This advancement enhances the reliability and accuracy of MEG system assessments.
